Keeping Pathogens Out: Step 1 of a Disease Prevention Strategy

Mark W. Bienhoff, DVM—Pathogen Control Team Leader, Kemin Industries

Infectious agents, or pathogens, are a threat to livestock and poultry health and even human health in some zoonotic situations. Pathogens that cause diseases also have significant economic implications, as well as negative effects on animal welfare. Keeping disease out of functioning production facilities is difficult due to the natural presence of pathogens, resulting in an endemic pathogen load. The goal of any biosecurity program is to (1) prevent the introduction of any infectious agent, (2) prevent or minimize dissemination of infectious agents within the facility and (3) minimize the impact of endemic pathogens that can cause subclinical disease.1 The purpose of this article is to summarize basic strategies and technologies that can be used to prevent disease from interring a livestock or poultry production facility.

Endemic, as well as pathogenic, contagious diseases can be transmitted between farms by various routes such as live animals, trucks and other vehicles, people, aerosols, fomites, wildlife and insect vectors.2 The frequency and/or contact patterns of these transmission routes can heighten the risk of disease introduction.3 To minimize these introductions, biosecurity routines must be put in to help reduce the probability of disease introduction and maintain the health and welfare of the production animals.

Importance of External Biosecurity

With the advent and increase of global travel and commerce, the possibility of an introduction of a foreign animal disease (FAD) into the U.S. livestock and poultry industries is enhanced. An Iowa State University study estimates potential revenue losses to the U.S. pork and beef industries from a foot-and-mouth (FMD) outbreak would run $12.8 billion per year, or $128 billion over a 10-year period. Additional losses to corn and soybean markets over the decade would also be sizable.4 Dedicated external biosecurity programs can help in preventing and containing the spread of an emerging epidemic disease.

Keeping pathogens out of a livestock or poultry production system is the first step for a disease prevention strategy and is considered one of the more cost-effective forms of health care. Published epidemiological modeling data would suggest that the most important indicator of biosecurity risk is the disease prevalence in the immediate area surrounding the production unit. It is well known that as disease prevalence/pressure rises, so does the risk for an outbreak. A suitable, isolated geographical location for a farm would be the most desirable. The second most critical factor is decreasing the number of contacts to potential outside pathogens. This can be accomplished through well-designed and implemented on-farm biosecurity programs. Third, the risk of disease introduction also depends on the infectious agent, as infectivity can vary dramatically between pathogens. These points support the importance of developing a biosecurity program, which accounts for the facility’s proximity to other animals, ability of the program to decrease outside pathogen contacts and recognize the characteristics of the pathogen to be avoided or eliminated.5

It is often said that disease enters into a facility on “two and four legs.” Additional biosecurity measures must be put in place to govern the movement of people and the animals/poultry coming into the clean production unit. The source and handling of the primary stock or birds must be monitored, and the disease status of placement animals fully understood. Transportation and movement should be provided with vehicles certified to be clean and properly sanitized.6

Kemin Pathogen Control Products and Programs

Kemin believes the initial environmental focus when drafting a comprehensive pathogen control program should include:

Assessment of the external biosecurity procedures in place to reduce contact opportunities with outside pathogens and prevent their entry into the production facility.

Standard cleaning (degreasers) and disinfection products, along with the accompanying procedures, should be used on premise surfaces. The goal is to provide a clean environment for livestock and poultry placement.

Water sources, lines and tanks should be free of pathogens and biofilms removed.

Livestock handling and transportation equipment must be cleaned and disinfected per accepted protocols. Proper drying of transportation vehicles must also be incorporated into the procedures.

Biosecurity protocols for incoming materials, supplies and feeds must be put in place.

Disinfection and sanitation of incoming materials and supplies is critical.

Feed pathogen control products should be considered for nutrition programs, which minimize the risk of disease introduction from potential contaminated ingredients or mill manufacturing sites.

Shipping and or transportation vehicles for incoming items must be verified as safe and clean.

Summary

As the livestock and poultry industries move toward disease prevention and control, increased emphasis must be placed on biosecurity programs to minimize the risk of pathogen transmission to healthy stock. Kemin promotes strong biosecurity programs that incorporate products and technologies which reduce contact opportunities and prevent pathogens from entering the production facility. Through development of on-farm protocols, which incorporate effective products and technologies, the goal of rearing livestock and poultry in a clean environment addresses our desire for optimum animal health and welfare.